Ageing Test Results of low voltage MOSFET Modules for electrical vehicles

IEEE Trans. Power Electron.

Alam

2014

A noninterfering measurement technique designed around spread spectrum time domain reflectometry (SSTDR) has been proposed in this paper to identify the level of aging associated with power semiconductor switches inside a live converter circuit. Power MOSFETs are one of the most age-sensitive components in power converter circuits, and this paper demonstrates how SSTDR can be used to determine the characteristic degradation of the switching MOSFETs used in various power converters. An SSTDR technique was applied to determine the aging in power MOSFETs, while they remained energized in live circuits. In addition, SSTDR was applied to various test nodes of an H-bridge ac-ac converter, and multiple impedance matrices were created based on the measured reflections. An error minimization technique has been developed to locate and determine the origin and amount of aging in this circuit, and this technique provides key information about the level of aging associated to the components of interest. By conducting component level failure analysis, the overall reliability of an H-bridge ac-ac converter has been derived and incorporated in this paper.Index Terms-Aging, converter, degradation, failure rate, matrix, mean time to failure (MTTF), reflectometry, reliability, spread spectrum time domain reflectometry (SSTDR).

Section: Origin Of Degradation In Power Semiconductor Devicesmentioning

confidence: 99%

Quantifying Device Degradation in Live Power Converters Using SSTDR Assisted Impedance Matrix

IEEE Trans. Power Electron.

Alam

2014

“…The ON-resistance of a power MOSFET has been described as the most significant aging factor in [15]. Die solder layer failures are related to formation of initial solder microstructure, substrate metallization, intermetallic compounds, and cracks.…”

Section: State Of the Art Solution To Identify Device Degradationmentioning

confidence: 99%

Real time monitoring of aging process in power converters using the SSTDR generated impedance matrix

2013 Twenty-Eighth Annual IEEE Applied Power Electronics Conference and Exposition (APEC)

2013

A non-interfering measurement technique has been proposed in this paper to identify aging in various components in a power converter circuit. Several power MOSFETs and IGBTs were aged in a controlled environment, and spread spectrum time domain reflectometry (SSTDR) technique was applied to these components to determine the associated level of electrical degradation while they were connected in an energized circuit. Multiple impedance matrices have been created based on the measured reflection across multiple node pairs of the circuit, and these reflections are the true representations of the impedance across those node pairs. Therefore, these matrices provide key information about the level of electrical degradation associated to the core power components in the power circuit, and it is possible to predict the remaining life of the power converter by using this impedance matrices.

“…Therefore, the change in the threshold voltage can be considered as the precursor to failure [3]. ON resistance was found to be the most significant aging factor of power MOSFETs [4], and two aging measurement techniques for power MOSFETs are presented in [5]. The first technique demonstrates aging by introducing a thermal overstress situation having a constant operational temperature.…”

Section: State Of the Art Solutions To Identify Device Failure Mementioning

confidence: 99%

Characterization of aging process in power converters using spread spectrum time domain reflectometry

2012 IEEE Energy Conversion Congress and Exposition (ECCE)

2012

Figure 1. The proposed technique to identify aging of various components using reflectometry without altering the main power flow of the converter.Abstract-This paper aims to find a new technique to predict the state of health of power converters by characterizing the most vulnerable components in the converter without affecting the normal circuit operation. Spread spectrum time domain reflectometry (SSTDR) can detect most of the aged components inside the converter while the converter is operational. Semiconductor switches and electrolytic capacitors are the two most sensitive components in power converter circuits, and this paper demonstrated how SSTDR can be used to determine the degradation of these components. Multiple sets of test data have been generated while the SSTDR process is applied to the power MOSFETs, IGBTs connected in a chopper circuit and to the aluminum electrolytic capacitors connected in an RC circuit. Analysis is done on these obtained test data to show how the SSTDR generated data are consistent with the aging of power MOSFETs, IGBTs and electrolytic capacitors. I.978-1-4673-0803-8/12/$31.00 ©2012 IEEE